Now the Lord said to Abram, “Go from your country and your kindred and your father’s house to the land that I will show you. And I will make of you a great nation, and I will bless you and make your name great, so that you will be a blessing. I will bless those who bless you, and him who dishonors you I will curse, and in you all the families of the earth shall be blessed.”
If you come to this passage with the categories of election and reprobation in your mind, you might misunderstand this passage. Abraham is not being chosen for salvation here (though he was so chosen before the foundation of the world) but for a new covenantal relationship and calling to bring salvation to the world. Genesis 12.1-3 is the Old Testament’s version of John 3.16. God loves the world (desires to bless all the families of the earth), therefore he calls Abraham.
That’s why this calling can be used by God not as the basis for absolutely guaranteed blessing for Israel, but rather for their punishment:
You only have I known
of all the families of the earth;
therefore I will punish you
for all your iniquities (Amos 3.2)
Excellent point. Israel was the “revelatory elect”, used by God in a covenant relationship so that “The nations will know that I am YHWH”. We see that phrase all throughout the O.T. Christ is the summation and fulfillment of that covenant. In Christ the promises to Abraham become “better” promises.
Heb 8:6 But as it is, Christ has obtained a ministry that is as much more excellent than the old as the covenant he mediates is better, since it is enacted on better promises.
Heb 8:7 For if that first covenant had been faultless, there would have been no occasion to look for a second.
Heb 8:8 For he finds fault with them when he says: “Behold, the days are coming, declares the Lord, when I will establish a new covenant with the house of Israel and with the house of Judah,
Heb 8:9 not like the covenant that I made with their fathers on the day when I took them by the hand to bring them out of the land of Egypt. For they did not continue in my covenant, and so I showed no concern for them, declares the Lord.
Heb 8:10 For this is the covenant that I will make with the house of Israel after those days, declares the Lord: I will put my laws into their minds, and write them on their hearts, and I will be their God, and they shall be my people.
Heb 8:11 And they shall not teach, each one his neighbor and each one his brother, saying, ‘Know the Lord,’ for they shall all know me, from the least of them to the greatest.
Heb 8:12 For I will be merciful toward their iniquities, and I will remember their sins no more.”
Heb 8:13 In speaking of a new covenant, he makes the first one obsolete. And what is becoming obsolete and growing old is ready to vanish away.